Device for piling rotor sheets for magnetic circuits of electrical machines

ABSTRACT

Device for piling rotor sheets for magnetic circuits of electrical machines comprising, a stationary mandrel provided with at least five grooves along its generating line which ensures orientation and lamination of the sheets; wherein at least one of said grooves houses driven rolls, two other grooves house chain conveyers with rollers for catching the sheets, and the last two grooves house, respectively, squeezing rolls to rotate the sheets and orienting means in the form of elastic spring-loaded keys, consisting of strips which are fixed in a row on a flat spring; said stationary mandrel being mounted in a support assembly provided with successively operating pairs of hollow rotating levers whose cavities contain gear trains to link kinematically said driven rolls and said conveyers of the mandrel.

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I eldshtein et al.

States Patent [191' MACHINES lnventors: Isaak Yaltovlevich Feldshtein, ulitsa Rymarskaya 23, kv. 5; Valery Sergeevich Epifanov, 605

DEVICE FOR PILING ROTOR SHEETS FOR MAGNETIC CIRCUITS OF ELECTRICAL Mikroraion, 20, kv. 22; Vladimir Fedorovich Isygankov, prospekt Pravdy, 7, kv. 160; Alexandr Nikitovich Pashkov, pereulok Rubezhansky, 24; Dmitry Gavrilovich Mogilny, ulitsa Sumskaya, 7/9, kv. 23; Mikhail Vasilievich Yakovlev, ulitsa Plekhanovskaya, 41/43, kv. 6, all of US. Cl 29/203 L Int. Cl. H05k 13/00, H02k 15/00 Field of Search 29/203 L, 211 L,

29/203 R, 211 R, 205 R Jan. 15, 1974 [56] References Cited 5 UNITED STATES PATENTS 2,658,268 ll/l953 Knauf, Jr. et al. 29/203 L Primary Examiner-Thomas H. Eager Attorney-Eric H. Waters et al.

[5 7 ABSTRACT Device for piling rotor sheets for magnetic circuits of electrical machines comprising, a stationary mandrel provided with at least five grooves along its generating line which ensures orientation and lamination of the sheets; wherein at least one of said grooves houses driven rolls, two other grooves house chain conveyers with rollers for catching the sheets, and the last two grooves house, respectively, squeezing rolls to rotate the sheets and orienting means in the form of elastic spring-loaded keys, consisting of strips which are fixed in a row on a flat spring; said stationary mandrel being mounted in a support assembly provided with successively operating pairs of hollow rotating levers whose cavities contain gear trains to link kinematically said driven rolls and said conveyers of the mandrel.

3 Claims, 6 Drawing Figures PATENTEDJAN 15 1974 SHEEI 3 OF 3 DEVICE FOR PILING ROTOR SHEETS FOR MAGNETIC CIRCUITS OF ELECTRICAL MACHINES The present invention relates to devices for piling rotor sheets for magnetic circuits of electrical machines.

Known in the art is a sheet piler used, in particular, to laminate stator sheets, which comprises a mechanism for stator sheet rotation and a.key for holding a rotating sheet in the oriented position.

The application of this sheet piler is limited due to the fact that is can only be used for piling stator sheets for electrical machines of low power. The application of this device for piling magnetic circuit sheets of medium and large-size electrical machines is rendered difficult because of a sharp reduction of sheet stiffness.

- Besides, such devices suffer from low efficiency since an orientation section can contain only one sheet at a time.

Known in the art are also devices for piece-by-piece orientation and piling ofmainly non-rigid rotor sheets for magnetic circuits of electrical machines, comprising a stationary mandrel, driver means for rotating these sheets about the mandrel at an orientation section and a spring-loaded key for orienting the sheets on the mandrel. These devices are characterized by low efficiency (single-piece production), while the effort to increase their efficiency involves the problem of designing heavily loaded mechanisms of discrete modes of operation.

The object of the present invention is to obviate the above disadvantages.

The invention aims at providing a device for piling rotor sheets for magnetic circuits of electrical machines, which will increase the efficiency of the lamination, orientation and piling procedures by carrying out these operations simultaneously.

This aim is achieved, according to the invention, by providing a sheet piler whose stationary mandrel has at least five grooves along its generating line with at least one of them housing driven rolls and the rest containing at least two chain conveyers with rollers for entrapping the sheets, an assembly of squeezing rolls to rotate the rotor sheets and an elastic spring-loaded key designed as a set of strips that are fixed in a row on a flat spring.

The stationary mandrel is mounted in a support assembly which is provided with alternately operating pairs fo hollow rotating levers whose cavities contain gear trains to link kinematically the driven rolls and the chain conveyers of the stationary mandel.

It is advisable that the-bottom section of the stationary mandrel be designed as a tube with a rigid orientation key located on the generating line of the tube, and with rotatable blocking detents that are mounted on the tube to serve for receiving the oriented sheets in the course of their piling.

It is also advisable that inside the section of the mandrel made as a tube, there should be placed a moving stem with a cleat provided with shoulders to control blocking detents, the stem being driven by two pairs of hollow rotating levers of the support assembly via a differential gear and gear trans housed in the cavities of these levers.

This device for piling rotor sheets for magnetic circuits of electrical machines, when compared with similar devices of the known design, has a higher efficiency of laminating, orienting and piling of sheets, it is applicable to piling sheets for magnetic circuits for rotors of electrical machines of all types, and proves to be particularly effective for piling non-rigid sheets having open grooves on their external surfaces.

Theinvention will be better understood from the following description of an exemplary embodiment with reference to the accompanying drawings, in which FIG. 1 is a plan view of an exemplary device for piling rotor sheets for magnetic circuits of electrical machines, according to the invention,

FIG.2 is a cross section along line II-II of FIG.I,

FIG.3 is a cross section along line III-III of FIG.2,

FIG.4 is a longitudinal section of a part of a key,

FIG.5 is a cross section along line V-V of FIG.I, and

FIG.6 is a cross section along VI-VI of FIGS.

The device for piling rotor sheets for magnetic circuits of electrical machines comprises a stationary mandrel l in the form of a tube (FIG. 1), one end of which is coupled with a mechanism for piece-by-piece delivery of the rotor sheets (not shown in the drawing), and the other end has a kinematic link with a driver assembly 2 that drives the operating elements of the stationary mandrel 1 through two pairs of lower andupper levers 3 and 4, serving also to hold the stationary mandrel 1.

To receive assembled packs of sheets the device is provided with a slidable or detachable receiving mandrel 5 (FIG.2).

The upper section of the stationary mandrel 1 has seven grooves which house, respectively, two pairs of driven rolls 6 (FIGS. 2,3) which rotate the sheets in the course of the orientation procedure, a set of squeezing rolls 7 ensuring the rotation of the sheets, three chain conveyers 8 with rollers 9 which are kinematically linked with the driven rolls 6 via a gear system 10, and an elastic spring-loaded key 11.

The driven rolls 6 are rotated by a driver shaft 13 via the gear system 10 and a toothed wheel 12.

The squeezing rolls 7 are arranged in pairs of springloaded and freely rotating, sections whose length is equal to the gap between the rotor sheets which are being transported.

The chain conveyers 8 with rollers 9 are made as vertically closed and kinematically interlinked gear trains. The rotational axes of the rollers 9 are arranged radially with respect to the mandrel at a pitch which is equal to that between the rotor sheets. The elastic key 11 (FIG.2) comprises a flat spring 15 (FIGS. 3,4), one end of which is attached to strips 16, and the other end is attached to guiding strips 17.

The gaps between the strips 16 and the rigidity of the flat spring 15 are selected so that the elastic key 11 biased along its total length with springs 18 (FIG.2), can camber within an area equal to or less than the distance between the sheets.

The movements of the upper and lower pairs of levers 3 and 4, respectively, (FIGS) are controlled by an electric motor 19 through a reduction gear 20 coupled with a shaft 21 which carries a master form 22 attached to it. The master form 22 (FIGS. 5,6) houses rollers 23 coupled with two cleats 24 and 25. The cleats 24 and 25, in their turn, are coupled via toothed wheels 26 and 27 with washers 28 and 29. Compensation assemblies 30 serve to eliminate gaps and play in the system.

Each of the cleats 24 and 25, via the toothed wheels 26 and 27, drives the washers 28 and 29 which have joint couplings, via rods 31, with the respective arms of the levers 3 and 4 (FlG.l). Located in the body of the support assembly 2 is a gear train which drives the driven rolls 6 (FIG. 2), the chain cony'eyers 8 with rollers 9, the upper and lower springloaded detents 32 and 33, respectively, whih are mounted in the bottom section of the stationary mandrel 1 made as a tube.

The rolls 6 and th chain conveyers 8 are driven by an electric motor 34 via a reduction gear 35, a shaft 36, bevel gears 37 and 38 upper and lower shafts 39 and 40 (depending upon the position of lever pairs 3 and 4), and shafts 41 and 42 whose toothed input wheels 43 and 44 (the lever pairs 3 and 4 being driven together and entrapping the stationary mandrel l) engage the respective toothed wheels of the drivershaft 13.

The blocking detents 32 and 33'serve to select a pack of sheets and to transfer it to the receiving mandrel while the process of orienting the sheets continues uninterruptedly. The upper spring-loaded detents 32 are controlled directly by the upper shoulder of a hollow stem 45 gliding inside the tube that serves as the bottom section of the stationary mandrel 1. To move the rolls 6 and conveyers 8 with rollers 9 the stem 45 is provided with grooves.

The lower detents 33 are controlled by the lower shoulder of the stem 45 which acts upon a bush 46 coupled with the detents through levers 47. The detents 33 are opened due to the action of the weight of the bush 46. Fixed to the hollow stem 45 is a cleat 48 which engages cylindrical gears 49 and 50 of rolls 51 and 52 located in the upper and lower pairs of the levers 3 and 4, respectively. The rolls 51 and 52 are kinematically interlinked through bevel gears 53 and 54, a shaft 55 and a differential gear 56. An upper toothed wheel 57 of the differential gear 56 is coupled with the lever 3 while the body of a planetary pinion assembly 58 is coupled with the lever 4 via cylindrical gears 59 and 60 and a toothed wheel 61.

The device operates as follows. Rotor sheets to be packed in a magnetic circuit of an electrical machine are fed piece by piece to the stationary mandrel l. Having arrived to the stationary mandrel 1 each sheet is centered on the driven and squeezing rolls 6 and 7 as to the position of its internal hole. Then, as soon as the succeeding descending rolls 9 arrive, each sheet starts moving. The required engagement between the sheet and the driven rolls 6 is provided by the pressure exerted onto it by the squeezing rolls 6. The sheet starts rotating and freely turns the rollers 9 that guide it downward. The stationary mandrel l is centered and fixed by the upper pair of levers 3. The lower pair of levers 4 is driven apart or separated.

In the course of displacement and rotation each rotor sheet glides along the external polished surfaces of strips 16 (FIGA) of the elastic key 11 (FlG.2). The sheet can freely move along the surface of the elastic spring-loaded key 11 because the gaps between the strips 16 (FIG.4) are substantially less than the thickness of the sheet, due to which the elastic spring-loaded key 11 bends and tends to straighten under the action of elastic forces. At the moment when the keyslot of the sheet coincides with the elastic spring-loaded kay 11 the latter straightens, thereby driving into the piling keyslot and holding the sheet, preventing it from any further rotation.

The diameters of driven and squeezing rolls 6 and 7 arranged in pairs, as well as their positions with respect to one another, are selected so as to exclude any delay in the courseof rotation of each sheet at the moment when it passes by the keyslot in the area of the driven and squeezing rolls 6 and 7. Then, the oriented sheet is pushed by the rollers 9 of the chain conveyer (FIG.2) 5 out onto the bottom section of the stationary mandrel 1 made as a tube which is provided with a fixed rigid orientation key coinciding with the elastic key 11. Thus the sheets which arrive in succession to the upper section of the stationary mandrel 1 are oriented and transferred to the upper detents 32 where they are arranged in afpack.

Just before the pack lamination procedure is over the electric motor 19 is energized. The rotation of the motor via the reduction gear 20 and the shaft 21 is transmitted to the master-form 22. The master form 22 starts rotating clockwise (FIG.6). At the same time the roller 23 of the cleat 24 that controls the upper washer 29 rolls along the track of a variable radius. The displacement of the cleat 25 is transmitted via the toothed wheel 27 to the upper washer 29 which used the rods 31 to draw apart the upper pair of levers 3.

Here, the roller 23 of the cleat 24 that controls the lower washer 28 rolls along the track of a constant radius. Hence, the levers of the lower pair of levers 4 remain stationary. The compensation assembly 30 eliminates any play in the train gears while the lower pair of levers 4 holds the stationary mandrel l with the preset force.

When the upper pair of levers 3 is driven apart or separated the cylindrical gear 49 of the roll 51 (F162) disengages the cleat 48. The upper toothed wheel 57 of the differential gear 56, which is rigidly coupled with a lever of the upper pair of levers 3, rotates the planetary pinions of the differential gear 56, the pinions turn the lower toothed wheel of the differential gear 56 and the shaft 55. The latter acts upon the cleat 48 through a bevel gear, the roll 52 and the cylindrical gear 50, and shifts the hollow stem 45 downwards.

When the process of driving apart the upper pair of levers 3 is over the shoulder of the hollow stem 45 will sink the upper blocking detents 32 and the pack of sheets will drop under its own weight until it reaches the lower blocking detents 33.

The moment when the upper pair of levers 3 is drawn apart corresponds to a clockwise displacement of the master form 22 through an angle of 1r/2.

Then, the levers of the upper pair 3 start pulling together. At the beginning of this process the upper blocking detents 32 are freed from the pressure of the upper shoulder of the hollow stem 45 and are shifted under the pressure of springs, thus allowing the lamination of the next pack of oriented sheets.

When the master form 22 turns through an angle of 1r, both pairs of levers 3 and 4 are driven together.

In the course of further clockwise rotation of the master form 22, the stationary mandrel l is held by the upper pair of levers 3 while the levers of the lower pair 4 are driven apart.

At the end of the process when the lower pair of levers 4 are driven apart (the master form 22 has turned through an angle of 3/2 1r) the movement, via the cylindrical gears 59 and 60 coupled with the right-hand lever of the lower pair of levers 4, is transferred to the set of planet pinions of the differential gear 56. The planet pinion set, while rolling along the stationary upper toothed wheel 57 of the differential gear 56, turns the lower toothed wheel of the differential gear,

the shaft 55 and the-rollSl. The cylindrical gear 49 of the shaft 51, acting through the cleat 48 and the lower shoulder of the hollow stem 45, raises the bush 46 which lowers the lower blocking detents 33, the bush acting through the levers 47.

The pack of sheets that has been piled up earlier and that has been kept in place by the lower blocking detents 33 moves now downward and reached the sliding (or detachable) receiving mandrel 5 from which the sheets are transferred to other operations.

Further rotation of the master form 22 will close the pair of levers 4, and by the time the latter makes a complete revolution (2 11) all the elements of the support assembly 2 get back totheir initial positions.

When the next pack of sheets is piled on the upper blocking detents 32, the lower 4 and the upper 3 pairs of levers repeat their operational cycle while the master form 22, making one more revolution, again intercepts the stationary mandrel 2 by the respective pairs of levers, and transfers the piled pack of sheets.

The automated process of transportation and orientation of the sheets on the upper section of the stationary mandrel 1 remains continuous since, irrespective of the position of the lower and upper lever pairs of 4 and 3, the driving shaft 13 is constantly rotated either by the shaft 41 or by the shaft 42 which is coupled with the rotating shaft of the electric motor 34 through a set of bevel gears, as well as through the shaft 36 and the reduction gear 35.

What is claimed is:

l. A device for piling rotor sheets for magnetic circuits for electrical machines, comprising: a stationary mandrel ensuring orientation and lamination of the rotor sheets; asupport assembly linked kinematically to said mandrel and provided with two pairs of hollow rotating levers that operate in turn; said mandrel having at least five grooves along its generating line; wherein driven rolls are placed at least in one of said grooves of the mandrel; at least two chain conveyers with rollers are placed in two other grooves of said mandrel; squeezing rolls, for rotating the sheets, are placed in the next groove of said mandrel; further comprising means for orienting the sheets, in the form of an elastic springloaded key, consisting of strips fixed in a row on a flat spring, said orienting means being placed inside the last groove of said mandrel; and gear trains located in cavities of said levers for linking kinematically said driven rolls and said conveyers of the mandrel.

2. The device as defined in claim 1, wherein the bottom section of said mandrel is made as a tube, provided with a rigid orientation key which is located on the generating line of said tube, and with rotating blocking detents mounted on said tube and serving to receive oriented motor sheets when they are piled in a pack.

3. The device as defined in claim 2, wherein said tube houses a moving stem with a cleat, said stem being provided with shoulders to control said blocking detents and driven by two pairs of said hollow levers of the support assembly via a differential gear and said gear trains located in the cavities of said levers. 

1. A device for piling rotor sheets for magnetic circuits for electrical machines, comprising: a stationary mandrel ensuring orientation and lamination of the rotor sheets; a support assembly linked kinematically to said mandrel and provided with two pairs of hollow rotating levers that operate in turn; said mandrel having at least five grooves along its generating line; wherein driven rolls are placed at least in one of said grooves of the mandrel; at least two chain conveyers with rollers are placed in two other grooves of said mandrel; squeezing rolls, for rotating the sheets, are placed in the next groove of said mandrel; further comprising means for orienting the sheets, in the form of an elastic spring-loaded key, consisting of strips fixed in a row on a flat spring, said orienting means being placed inside the last groove of said mandrel; and gear trains located in cavities of said levers for linking kinematically said driven rolls and said conveyers of the mandrel.
 2. The device as defined in claim 1, wherein the bottom section of said mandrel is made as a tube, provided with a rigid orientation key which is located on the generating line of said tube, and with rotating blocking detents mounted on said tube and serving to receive oriented motor sheets when they are piled in a pack.
 3. The device as defined in claim 2, wherein said tube houses a moving stem with a cleat, said stem being provided with shoulders to control said blocking detents and driven by two pairs of said hollow levers of the support assembly via a differential gear and said gear trains located in the cavities of said levers. 